Certain embodiments of the present invention generally relate to an electric connector for transporting power and electric signals. More particularly, certain embodiments of the present invention relate to a surface mount connector that provides a separable interface between a printer connector and a substrate.
A typical inkjet printer includes a printer cartridge that is controlled to dispense certain colors and amounts of ink onto paper in particular patterns. The colors and patterns are controlled by power and data signals supplied by the printer to the printer cartridge. A printer cartridge connector system connects the printer cartridge to a circuit board within the inkjet printer in a manner that allows the printer cartridge to be easily replaced. The printer cartridge connector system comprises a pen connector, a printer connector, and a pen substrate. Inkjet printers provide power and data signals through the circuit board to the printer connectors, which in turn convey the power and data signals through the pen connectors to the pen substrates to dispense certain colors and amounts of ink onto paper.
A conventional printer cartridge connector system exists that utilizes a printer connector that transfers power and data signals from a circuit board to a pen housing. The pen housing includes a pen assembly and a pen substrate. The pen substrate is aligned perpendicularly to the pen assembly. The pen assembly includes a flexible film cover that extends along a front surface down to the pen substrate which is located on a bottom surface perpendicular to the front surface. The flexible film contains contact pads that receive power and data signals from the printer connector and are connected to the pen substrate by wire traces located within the flexible film. The wire traces are wire bonded or soldered to the pen substrate and carry the data and power signals from the contact pads to the pen substrate.
The conventional printer connector includes a housing, compressive springs, and plunger contacts. The housing is mounted on the circuit board and includes a front surface containing apertures. The springs are located within the housing in alignment with the apertures and contact the printed circuit board. The plunger contacts extend out of the housing through the apertures and are retractable into the housing.
In operation, the circuit board conducts power and data signals from the printer to the springs. The pen housing and printer connector are aligned with each other within the printer cartridge connector system so that the plunger contacts touch the contact pads and are pushed into the housing of the printer connector in electrical contact with the springs. The plunger contacts then conduct the power and data signals to the contact pads which, in turn, conduct the power and data signals down to the pen substrate via the wire traces.
The printer cartridge connector system suffers from several flaws. First, the printer cartridge connector system as a whole involves too many discrete components that are both delicate and intricate, which creates a large risk of failure or damage. Second, the printer connector housing is bulky and takes up more space within the printer cartridge connector system than desired. Third, a separate wire trace is needed to connect each contact pad to the pen substrate, thereby creating a large collection of wire traces within the flexible film. Also, wire bonding each wire trace to the pen substrate is a time consuming and delicate process. Finally, the flexible film cover used to retain the contact pads on the front surface of the pen housing is expensive.
Thus a need exists for a printer cartridge connector system that connects a printer connector surface to a perpendicular pen substrate without taking up a significant amount of space or requiring several intricately connected components.
Certain embodiments include an electronic cartridge connector assembly for conducting power and data signals from a printed circuit board to a substrate. The connector assembly includes a housing adapted to be secured to an electronic cartridge. The connector assembly also includes contacts secured to the housing and adapted for carrying power and data signals to the electronic cartridge. Each contact has a tail end adapted to be bounded to the substrate and a connector pad at an end opposite to the tail ends. The connector pads are adapted to electrically engage mating contacts. The tail ends are held within the housing in a first plane and arranged in rows spaced apart by a first distance. The connector pads are held within the housing in a second plane arranged in rows spaced apart by a second distance. The first distance and the second distance differ from each other.
The first plane and second plane may intersect each other, and the tail ends of the contacts may be directly connectable to a substrate surface by reflow soldering. The tail ends may be arranged in at least first and second rows having respective first and second center lines spaced apart by the first distance, and the connector pads may be arranged in at least first and second rows having respective first and second centerlines spaced apart by the second distance.
Each contact may include a stem portion extending from the tail end to the connector pad. The stem portion includes a flared retention barb that is wider than the stem portion. The flared retention barb frictionally engages the housing in order to retain a corresponding connector pad within the second plane by resisting normal forces experienced by the corresponding connector pad from a mating contact. Each contact may include a retention beam that extends from the connector pad. The retention beam is snapably received into a recess in the housing in order to resist normal forces experienced by the connector pad from a mating contact. Each stem portion includes an alignment arm that extends transverse to a longitudinal axis of the stem portion. The alignment arm is located along the stem portion and relative to the tail ends so that when the alignment arm is received in a transverse slot in the housing, the alignment arm locates the tail end in the first plane.
In certain embodiments, at least one contact may include an alignment member spaced a predefined distance from the tail end. The housing may include channels that receive the contacts, and at least one of the channels may have notches therein to receive the alignment member. The notches and the alignment member cooperate to locate the tail end in the first plane. Each stem portion further includes an enlarged segment configured to be releasably joined to a carrier strip before the contacts are secured to the housing. The enlarged segments are aligned in a common plane proximate a rear face of the housing, and the contact pads are aligned in the second plane proximate a front face of the housing.
In certain embodiments, the housing further includes a plurality of channels aligned parallel to one another and opening through a rear face of the housing. Each of the channels has an open bottom end that exposes the tail ends of the contacts, and each of the channels communicates with a hole that extends through a front face of the housing. The holes expose the connector pads through the front face. The channels are of alternate length. The channels separate the holes from the bottom ends by alternative distances. The channels may include support members that traverse the channels and support the contacts.
Optionally, in certain embodiments, the electronic cartridge connector assembly further includes a printer connector that has a plurality of slots that retain an equal plurality of spring contacts therein. The spring contacts have first ends secured in corresponding first ends of the slots and second ends that are biased outward from the second ends of the slots. The second ends of the spring contacts directly electrically engage the connector pads. The spring contacts are deflectable inward toward the slots, and the first ends of the spring contacts are configured to be directly soldered to a printed circuit board.